Please note that there is no current method to treat temporary HP gain in Elements. Temporary attack gain as in the case of Dive and Sky Blitz are executed by lowering the creature's CURRENT attack stat to be equal to its MAX attack stat. If this is duplicated for HP, it will mean any creature that is damaged can never be healed back - except self-inflicted damage like unupped Pandemonium or Rage Angel.
Anyway, I don't see much point in the +2 to HP except with X|1 creatures versus Fire Shield... and even then it may not save their lives. The +2 is lost when your turn ends, so it won't help make your creatures sturdier against enemy damage CC or Otyughs.
I assume these do not stack if you have several on the field, but even so... 4
|6
is too pricey for the effect. 3
|3
seems like enough to me, maybe even less, and the upped doesn't need to cost more. You're already paying extra for activating the creature's ability each turn, the attack boost doesn't linger, and 2
is just too much for 1 more attack. The way it is now, the unupped is more valuable than the upped, even in upped decks.
As requested, here's a deck using your card idea:
Hover over cards for details, click for permalink
4t6 4t6 4t6 6qq 6qq 6qq 6qq 6ts 6ts 6u3 6u3 6u3 6u3 6u6 6u6 6u6 6u6 6u6 6ve 6ve 7jp 7jp 7jp 7jp 7jp 7jp 7q1 7q1 7q1 7q1 8pj
Deja Vu/RoL Mutants. Dejas should of course be copied first, unless something threatens to remove them before mutation... every time you activate an Elf or mutant, you will get +2 attack on that creature. RoL will generate some
to cast Adoration with, and Quantum Towers ensure constant use of abilities. I only put three Adorations in there, since any further ones are dead draws if they don't stack.